This invention relates to clamping boards, particularly wooden boards, which are being glued edge-to-edge to form a panel. Such panels are commonly prepared by cabinetmakers in the course of building furniture such as case goods, table tops, cabinet panels and by carpenters in the course of building and remodeling homes. The usual procedures in constructing such panels begins with planing of all the boards for a panel to the same thickness. The boards are also planed on their edges. Glue is applied to the edges and the boards are clamped transversely, i.e., across their grain, to squeeze the glued edges together while the glue cures. Conventional clamps are available for this transverse clamping.
In spite of careful attempts (e.g., staggering transverse clamps above and below the panels) to avoid buckling, warping or cupping of the panel induced by the transverse clamping force, typically, the finished, glued panels are not flat. Because the panels are generally wide, they cannot be planed flat in conventionally available planers. Moreover, planing a warped panel undesirably reduces the panel's thickness and exposes different wood grains and the glue joints. In large quantity production shops, an attempt is made to prevent warping by stacking the gluing panels on top of each other and weighting or compressing the stack with a heavy, stationary press. But I am not aware of any clamp suitable for use in small-quantity production shop, at on-site jobs or in home workshops which deals with the problem of panel warping during gluing.
The present invention provides a simple, easy-to-use, inexpensive and portable panel clamp which prevents warping of a panel during the gluing of boards to form the panel without interfering with the transverse clamping of the glue joints. The invention is described with reference to a preferred embodiment which is depicted in the figures of the drawings.